diff options
author | David S. Miller <davem@davemloft.net> | 2009-09-24 15:13:11 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2009-09-24 15:13:11 -0700 |
commit | 8b3f6af86378d0a10ca2f1ded1da124aef13b62c (patch) | |
tree | de6ca90295730343c495be8d98be8efa322140ef /arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c | |
parent | 139d6065c83071d5f66cd013a274a43699f8e2c1 (diff) | |
parent | 94e0fb086fc5663c38bbc0fe86d698be8314f82f (diff) |
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Conflicts:
drivers/staging/Kconfig
drivers/staging/Makefile
drivers/staging/cpc-usb/TODO
drivers/staging/cpc-usb/cpc-usb_drv.c
drivers/staging/cpc-usb/cpc.h
drivers/staging/cpc-usb/cpc_int.h
drivers/staging/cpc-usb/cpcusb.h
Diffstat (limited to 'arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c')
-rw-r--r-- | arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c b/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c new file mode 100644 index 000000000000..43ea80190d87 --- /dev/null +++ b/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c @@ -0,0 +1,64 @@ +/* linux/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c + * + * Copyright (c) 2009 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C24XX CPU Frequency scaling - utils for S3C2410/S3C2440/S3C2442 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/cpufreq.h> +#include <linux/io.h> + +#include <mach/map.h> +#include <mach/regs-mem.h> +#include <mach/regs-clock.h> + +#include <plat/cpu-freq-core.h> + +/** + * s3c2410_cpufreq_setrefresh - set SDRAM refresh value + * @cfg: The frequency configuration + * + * Set the SDRAM refresh value appropriately for the configured + * frequency. + */ +void s3c2410_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg) +{ + struct s3c_cpufreq_board *board = cfg->board; + unsigned long refresh; + unsigned long refval; + + /* Reduce both the refresh time (in ns) and the frequency (in MHz) + * down to ensure that we do not overflow 32 bit numbers. + * + * This should work for HCLK up to 133MHz and refresh period up + * to 30usec. + */ + + refresh = (cfg->freq.hclk / 100) * (board->refresh / 10); + refresh = DIV_ROUND_UP(refresh, (1000 * 1000)); /* apply scale */ + refresh = (1 << 11) + 1 - refresh; + + s3c_freq_dbg("%s: refresh value %lu\n", __func__, refresh); + + refval = __raw_readl(S3C2410_REFRESH); + refval &= ~((1 << 12) - 1); + refval |= refresh; + __raw_writel(refval, S3C2410_REFRESH); +} + +/** + * s3c2410_set_fvco - set the PLL value + * @cfg: The frequency configuration + */ +void s3c2410_set_fvco(struct s3c_cpufreq_config *cfg) +{ + __raw_writel(cfg->pll.index, S3C2410_MPLLCON); +} |